Author(s): MASSIMO GUERRERO, SLAVEN CONEVSKI

Linked Author(s):

Keywords: ACDP

Abstract:

This Chapter summarises the principles of underwater acoustics which are useful to ADCP users.Those can be found in great details within specific literature [e.g.,99, 117, 194]. The objective is tosort out and provide the fundamental and complete information to assist deep understanding ofmore specific parts of this monograph focusing on sediment transport quantification (i.e., Chapters3and 4). Section2.1 summarizes fundamental of continuum fluid mechanics and physics of vibration(i.e., sound pressure waves into water). This is an introduction to basic concepts and parameters(e.g., phase speed) that may appear unnecessary for this technical Monograph although are funda-mental to the understanding of following chapters. Section2.1 is mostly aimed at providing usedterminology later on. Then theoretical acoustics subjects close to ADCP applications are described:(i) scattering and reflection by underwater targets (e.g., the riverbed and suspended sediment inthe water column) in Sections2.2 and 2.3, respectively and, (ii) transmission loss due to water vis-cosity along ranging distance in Section2.4. Furthermore, this Chapter gives an overview about thetransducer properties (Section2.5) and signal processing techniques (Section2.6) which enableADCP generating well focused sound pulses underwater. Theoretical and more practical informationare therefore combined and finally summarised in the presentation of the ADCP layout (namely theJanus diverging beams configuration, Section2.6.2) and the Sonar Equation (Section2.7) that are thebases to eventually build and validate site specific methods for sediment transport quantificationusing this device.

DOI: 10.64697/iahr.watermonograph.010.ch02

Year: 2026